She was told that she had a further ten days to pay up in full or face disconnection - and if she was disconnected, she would have to stump up an extra £235 in costs.
She was previously a British Gas customer and has lived at the house since 1996. The letter was sent to her address, although it was addressed to a different man.
"We apologise for the worry caused to Mrs Banks. We have now rectified the situation both for Mrs Banks and the person whose name is on the correspondence," a spokesperson from British Gas told the East Anglian Daily Times.
"We assure Mrs Banks that no further correspondence will be received from British Gas and that her property is under no threat of disconnection."
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